Rag grinding machine



June 23, 1931. E. LANGEA 1,811,549

RAG GRINDING MACHINE Filed June 26. 1950 e 1 "L" Lr a4 4%. j" 5 fa 'wwwl i Patente-drJune 23, Y1,931` 'p i' fi i 1,811,545

F a f'enenanaanem '0F aannam* Appiicti'on. mea 'Juneu 26 '1930, seienJN0.

l quickly rotating drum or svvit 'studded' with sharply pointed v,steelpins, and cooperating vvith a pair ofvrollers by which the rags arefedlinto Athe machine and are supported Vduring the tearing `action.VV Yy Y 'llie'drurnsv ofrag devilsusually consistof a cylindrical innershell carried by ,spokes and naves on a rotarysha'tt, and of anfoutervcoatlconsisting of aoplurality of y hard Wood so-calledlags'detachablymounted 2U by screws. and rings onthecircumferential" surfaceof saidshell, the pointed steel `pins* being fastened Within and projecting'from thesaid lags.

` As a mattergof l v in this eldthe pinssoon lose their 4sharp pointsand tearing capacity whereby the out-' 1 piity ofthe`machineis-considerably1 reduced,

and the driving powverconsumed is ,highly in i t j creased inasmuch asthe rags.v presented tothe drum instead of being readily "openedfup are.

Y gathered and transformed int@ a padV which lets like akbralshoe.v t iY f improved ragvgrinding niachinethe drumof Which .can be held in.proper Working order and repair at considerably smaller `expense y thanit ywas' possible heretofore, inasmuch as less time and smaller. Wagesarerequired, for` i replacing Wornvpins by vne'vvvones, and. as the d cthe case of totore.- l .v Y .m Y, Y

e Another object of the invention isto thus design the drum (about 20%)more) at its `ci rcumference when fearknwriiw vacationers The object@fuit invertida is werden@ an f o cost of spare parts requiredorleep-ingthe improved'machines in; repair isjlower than-jin rag .grindingmachines used here-i A points; in' practice theoperator ofthe plantrmust @ber putfup Withthe drawback which i of the i1nproved'rag;grindingmachine that it :can befstudded with a considerably .larger number of.steel `pins i compared Withjmachineshaving Wooden attached to `4theirdrum, and that the elliciency 463,5384, aiidin- -eeniay inerti; en 19301y cordingly.

The invention als ha the output ffent mme i5 insect.'saiaia-- y am@aepfoviaing proved feed `and lrag rsupportingrollers for rag grindingmachines, cooperating Withthfe rotary drum by `wvhich the everthreatening danger Ais eliminated y resulting troni fthe .tendency of.the opened upc-highly inflammable materialf to catch lre'lifr'om sparks`proj-V duced through'accidentail :frictional contact Voi steel :pinsvyith the feed Vand supporting rollersof steel as used heretofore.

Farther: ,bife aim@ t. mid" advantages t I obtained by the invention-vvilllbeincidentally eppefethrfiftr?1 f e The nature and sco ejotth'isinventionf'are briefly outlinedl .in the appended-V claiinsand Willmorel fully understood from the `atollowing specification taken togetherwith the @CCO-Iipllyiileidrewingsin .which Figs. l andl 2 are sideelevations inl full scale showing my improved fsteel pins integrallyassociated withreaoh' other 'in Ythe -form of" toothed llo-lades and"beingl adapted :to be arid fifi Special materiali detachably ii'xed'inholders `otspecialdesig/n i Fig` is-aperspective viewV of the'bladeholdersrshowingalso the keys `for lock-` ing the toothed blades in'their Workingqgo-` sition, Y

Figl` f4 is a hlrs;

Vorethe lpinsl'ocated in other sections towards bothffendsp the drumhavelost their sharp consists therein that =a` large proportion of planVof one :ofthe Fgc 5 is a cross section throiighthe` andragijsupportingrollers reducedecale,` t illustrating their Cooperationwiththe grind-"the-output of the V-I'nachine vis reduced, j while its .driving powerFrequ-ired i is i increa'sede-o'r he mustj'have replaced; the Wholenumber `of Wooden lags in 'which the steel pins. are fas-` tened by newones, which means high eX- penses and interruption of the work for aconsiderable length of time.

I have overcome the said drawbacks by providing small sets or units ofpins integrally associated with each other in the form of toothed blades10, stamped of sheet metal such as steel, phosphor bronze, etc., andwhich are thus designed that each blade can be singly iiXed on anddetached from the rotary drum without dismounting the latter or theblade holders. V i

As seen in Figs. 144 the toothed blades 10 are formed 'with holes 11, 11of dove-tail shape and are adapted to be inserted into narrow slots 21of holders 2O and to be locked within the latter by keys 22 sliding inkeyways 23 of the holders 20.

The blade holders 2O are attached in juxtaposition to each other to thecircumference of the rotary drum and may be secured by any suitablemeans-e. g, by screw bolts 24, 24'; it should be noted that none of theholders needs to be detached while any of the blades 10 areexchanged-because the latter are inserted in radial direction relativelyto the drum and can be'detached simply by partly withdrawing their keys22.

My experiments have shown that wooden lags-as used heretofore, even ifmade of the hardest and toughest kind of wood, will not withstand themechanical strain resulting from the frictional contact between thetoothed blades and the rags and the centrifugal forces implied to thetoothed blades through the quick rotation of the grinding drum.

In order to carry my invention into eiect in practice I provide bladeholders made of aluminum alloyed with reinforcing metals such as copper,magnesium,-etc., known in the trade e. g. as duralumin, electron,Monelmetal which are at the same time strong as to their mechanicalstrength and light in weight.

As a matter of fact only by the application of blade holders of metalwhich is strong and light in weight toothed blades can be lused astearing elements which are so closely assembled in juxtaposed positionas shown in Figs. 3 and 4.

It should be noted that there is substantially no space left freebetween the pins at the seam lines where any two of the holding platestouch each other-or in other words there are no boarder sections free ofpins as in the case of wooden lags in which no pins cnbe inserted closeto their longitudinal e ges. j

The specific number of pins or teeth per square foot presented by myimproved rag grinding drum and correspondingly the output of the machineis therefore considerablyabout 20%-higher than in the case of machineshaving wooden lags as pin holders.

Another important feature of this invention is the provision of feed andrag supporting rollers of special design. In contradistinction to solidsteel rollers used heretofore my improved rollers are provided with acoat of indiarubber, or like elastic material.

In the embodiment of my invention shown in Fig.' 5 the feed and ragsupporting rollers concerned consist of steel cores 30, 40 having anintermediate layer of hard indiarubber 31,

`41, firmly attached by vulcanization, and a coat 32, 42 of a softerkind of indiarubber which should be rather tough and hard enough to Wellwithstand the wear to which it is subjected.

The indiarubber coats 32, 42 are preferably corrugated at their workingfaces, i. e. provided with longitudinally extending grooves and ridgesas in the case of solid steel rollers.

My experiments have shown that no sparks are produced by accidentalfrictional contact of the grinding drum with my improved feed and ragsupporting rollers, and that the danger of the opened up highlyinflammable material catching iire from sparks or causing realexplosions is eliminated.

Various changes and modification may be made in the construction of theimproved rag grinding machines described without substantially departingfrom the spirit and the salient ideas of my invention. d

E. g. the slots 21 provided in the blade holders 20 may be arranged toadvantage at a small angle to their equatorial line of symmetry fr asseen in Fig.

The keys 22 may be made in two pieces to be inserted from both ends ofthe blade holders 20.

.ICO

Means may be provided for locking the keys 22 `in their workingposition; my eX- periments however have shown that eXtra locking meansfor this purpose can be dispensed with and that the keys are in factself locking, showing no tendency to become displaced even through heavyshocks and vibrations to which the grinding drum is occasionallysubjected through rags containing hard aiticles such as buttons,buckles, hooks and the li ze.

In case of accidents caused by hard articles and resulting in bending orbreaking off a number of teeth of the blades only the damaged blades-noothers-need to be eX- changed, a manipulation which can be easily andquickly performed in the manner described.

The teeth of the blades may be formed to advantage with rounded corners10a at their lower portion as indicated in Figs. 1 and 2.-I have foundthat the mechanical strength of the teeth against bending and breakingis j thus better preserved and is higher than in being made of analuminium alloy the blade holders may be made integrallyvin one pieceWith the drum and the latter-#includin the i blade holding elementsf-maybe made o any suitablematerial which is light in Weight and has a highfactor of strength.

WhatIclaimis: l. In a rag grinding machine of the type described, i. e.having a rotarygrinding drum studded With sharply pointedk pins andbeingcooperatively associated With rag feeding and supporting rollers,ya drum presenting at its cylindrical'surfaceslots which eX@ tendsubstantially parallel to the direction of the equatorial .line ofsymmetry of the drum and transverse grooves, which extend substantiallyparallel to the axis of the drum, Y toothed blades having holes providedtherein and being adapted to be'inserted into the said. slots in radialdirection relatively to the drum, keys adapted to be inserted into thesaid transverse grooves (key Ways) ,so as to detachf y ably secure thetoothed blades in their vvork-V ing position at the drum, and ragfeeding andv supporting rollers having aninner core of metal and anVouter coat of non-metallic elastic material. Y

2. A rag grinding machine having the features outlined in claim l, inWhich the toothed 3o blades are provided With dove-tail shaped holescorresponding as to their size, form and position to the keyvvays andkeys concerned of dove-tail shaped cross section.

3.x Rag grinding machine having the features outlined in claim l, inWhich'the blade holding elements of the rotary drum are made of analuminium alloy.

4. Rag grinding machine having the feav tures outlined in claim l, inWhich the slots l o for the reception vof theV toothed blades arearranged at Aa small angle to the equatorial line of symmetry oftherdrum.-

5. Rag grinding machine having thev features outlined in claiml, inWhich the toothed blades are formed With rounded corners at .v the loWerpart of the teeth.,V Y

6. Rag grinding machine having the fea? tures outlined in claim l, inwhich therag y feeding and supporting rollers are provided With anintermediate layer of hard indiarubber arranged between the inner coreof steel and the outer coat of non metallic elastic material.

In testimony whereof I have signed my name to this specification. Y

' EDUARD LANGER;

